Polyphony and CV modules

Hi, I’m not a Mod user yet but very familiar with a similar legacy concept, the Nord modular. From there I know there’s some intricate trickness regarding polyphony and virtual cv-methodologies. In the Nord Modular systems there are two areas one for polyphonic and one for monophonic and it makes a lot of sense although it’s a bit too elaborate to explain in text here.

So my question is, how do for example the Mod the cv modules handle polyphony? Are they all monophonic, so I would need say four of each modules (osc, vcf, env and so on) to make a 4-voice patch and so on? Or can I add multi voice modules where the voices are encapsulated in one unit?


CV signal in LV2 (and MOD) is mono-phonic. It works similar to a regular audio buffer (it runs continuous, not at control-rate), except it can have additional properties like a voltage range (normal audio is -1 to +1, CV can be all kinds of ranges).

So correct, at the moment you’d need to make separate connections to each. Think of it more like a regular physical modular CV connection.

I have thought about some possibility to use single groups of CV modules to define a voice with like pitch/gate/mod that you could patch 1:1 - however this would be some sort of convention and not a real “standard”.

It might be possible to extend the CV specification with polyphony (thinking similar in usage as VCV Rack internal patching). However it is unlikely that someone will implement something like that any time soon.

Btw I can’t find any such polyphonic connections in Nord Modular docs: https://www.nordkeyboards.com/sites/default/files/files/downloads/manuals/nord-modular/Nord%20Modular%20English%20User%20Manual%20v3.0%20Edition%203.0.pdf

I believe that polyphonic synths in Nord Modular are simply controlled by MIDI signals, not by CV/modulation.
It is exactly how Axoloti is also implemented: a sub-patch defines the voice structure, and then the instance of that patch is set to a polyphonic with then a MIDI signal controlling the polyphonic voices.


Thanks for the info.

The solution in Nord Modulars is indeed polyphonic in the so called ”Poly voice area”. although you only see one of each module, there are as many as the polyphony. There are three main types of ”cv” internally; logic, audio and control. Midi only happens at the physical inputs and outputs. The system is very clever. I’ve never tried VCV, maybe it’s similar? Running something like that on Mod would be great.

I still don’t see any such “polyphonic modulation” in the Nord Modular documentation though … so your request doesn’t make much sense to me.

Can you show some actual examples so we better understand?

For MOD we have Cardinal, which is based on VCV Rack code: Cardinal Mini - MOD Audio

It has CV i/o, but again: CV ports are monophonic. (it also has MIDI i/o)

Each patch in the Poly Voice Area is one voice of the polyphony. So (if you have 6 voices) each time you repach a cable you are repatching six cables, each time you twist a knob you twist six knobs. Some modules (like random generators and lfo:s) can be set to act either independantly (each voice of it’s own) or together (monophonic identical behaviour, like it’s one module). Oscillators, filters e.t.c. are also independant and can be set to not act synchronized (modulation from a poly lfo/rnd is one example) although you still see only one module, use only one of each cable, knob, etc.

Then these voice meet in the Common Voice Area for typical effect treatments, mixing e.t.c.

Will check Cardinal, thanks.

Except that all happens “under the hood”. With MOD we are “above board” so to speak.
What happens with Nord Modular (and similar with Axoloti) is that it copies all these instances inside the module, but from outside you don’t have anything like "polyphonic control’ as such. Any per-voice activity happens only inside the abstracted module, not outside.

Cardinal is your best bet to patch polyphonic modular inside the MOD environment (and control polyphonically using MIDI, just like you’d do with Nord Modular)

CardinalMini has only a small set of modules (still to be expanded) and aims to have full polyphonic capabilities (so only poly modules are considered for future inclusion. that’s the main focus at least)

I’m not sure why you put quotes on that, I never wrote or ask for that specifically. Rather it was the abstraction of many voices into one module I was mainly interested in. But anyway, I got the general picture - so all fine.

(Just for the sake of completeness: In the G2 version of Modular you can put modules that will inform each voice of it’s voice number so there are some ways to achieve polyphonic control with logical operations there actually. For full polyphonic control you have to use the Common Voice Area as in Mod though. Often runs out of resources fast, they are old machines now.)

Because you explicitly asked about CV in this topic and your comparison with Nord Modular doesn’t really hold up :slight_smile:
I assume that in Nord Modular any controls do not run at audio-rate either.

While on paper polyphony for CV connections sounds interesting, I think in practice it would be quite hard to implement. But who knows maybe it could be possible in the future? :person_shrugging:

This was not meant as a competition between Mod and Nord so if it ”holds up” is completely irrelevant and I have no idea what audiorate has to do with anything but if you’re interested you can patch an audio source to a control (similar to cv) input in Nord.

I simply wondered if the cv cords and modules in Mod where polyphonic like on Nord. They weren’t but thats okay.

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Except in Nord they also do NOT seem to be polyphonic. (none of the manual or examples seem to exemplify this at all)

Can you please point to information that shows this, otherwise we have to take you on your word and it’s really confusing for me right now.

The way I understand it (and what has been copied to Axoloti) is that you can instantiate a polyphonic subpatch, but that does not give polyphonic (individual) control to the voices that are inside (other than through say a midi gate signal that instantiates individual LFOs or something)

All the docs I read about Nord Modular says it has a separate “poly area” in the patch where such connections are made. Which is very different from the mono-phonic voice-structure itself.

In that sense you could see the CV cables in MOD as being the “common voice area” in Nord Modular. And there is no superseding “poly area” where you can instantiate a polyphonic version of your patch/pedalboard.

Hmmm… seems like the misunderstanding here is that you interpret “polyphonic” as per voice individual control. With that interpretation of polyphonic basically just a few synthesizers are polyphonic like the Oberhem 2/4/8-Voice, custom made polyphonic modular setups and drum machines like TR808.

My interpretation, in my question, was the traditional definition of polyphonic; many voices, one control for all, one “cord” for all e.t.c. That’s why I never wrote polyphonic control in my question.

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Well there are different ways to do describe polyphony, and Nord Modular has an extremely peculiar way of achieving that.

Anyway know you know that CV modules are kind of “real world”. So it’s just like a regular modular system: 1-to-1